Animal Facts: Killer whale

Fast Facts: Killer whale

Did you know?

The southern British Columbia resident population of the killer whale is endangered.

Physiology

The killer whale is the largest member of the dolphin family. It has a distinctive black and white pattern, with a blunt head and tall dorsal fin that is triangular in shape and in the middle of its back. The maximum recorded length for a male is 9.0 metres, and for a female it's 7.7 metres. However, whales in the British Columbia population tend to be much smaller.

Habitats/Behaviours

Killer whales live in any ocean between 0 degrees Celsius and tropical water temperature. The depth of the ocean doesn't affect them—they have even been known to enter rivers. Killer whales travel in pods, which normally consist of a mother and her offspring. Resident pods can have up to three or four generations in one pod. Male calves born into a resident pod do not leave their mother's pod. Females, on the other hand, may form sub-pods with their own offspring later on in life. Transient whales don't always stay with a group for life. Either sex may leave their mother to travel, either alone or with another transient group. There are normally only two to six whales in a transient group, but it can reach up to 20.

There are three distinct types of killer whales: resident, transient and offshore. Resident killer whales travel in relatively stable groups called pods. They were coined as "resident" because they are seen each summer. There are about 600 whales in the resident population between Washington and Alaska, and they all feed on fish. Transient whales are those who travel in small groups and who are normally in transit. They eat mainly mammals, differing from the resident whales. There are about 400 transient whales that range from southern California to the Aleutian Islands of Alaska. Offshore whales are a bit more mysterious than the previous two types. They are rarely seen in British Columbia and could possibly be distant relatives of the resident killer whales. Offshore killer whales seem to feed on fish and squid. There are about 200 off-shore killer whales catalogued thus far.

There are three types of sounds that all killer whales produce: clicks, whistles and pulses. Clicks are used to detect and pursue prey, while whistles and pulses are how they communicate amongst themselves. Residents have seven to 17 calls that very between pods. Transients only have four to six, none of them used by residents.

Range

Killer whales are found in all three of Canada's oceans, and have even been known to enter Hudson Bay and the Gulf of St. Lawrence. They are, however, uncommon in the Atlantic and Arctic oceans. They are most often seen off the southern coast of British Columbia.